On Dec. 21, Pope Benedict XVI spoke about the dangers of the new theories of 'gender.' He explained how the very notion of what it means to be human is being called into question. According to the ideology of gender, sex is no longer a given element of nature that man has to accept and personally make sense of: it is a social role we choose for ourselves.

In the past the word 'sex' referred to the reality of being male or female. 'Gender' was a grammatical term. Some words had gender -- masculine, feminine or neuter. Recently, however, new and contradictory meanings have been given to 'gender.'

1) Gender as a synonym for sex -- Many people assume that the word gender is simply another more polite word for sex, preferable since sex is a shortened form of sexual intercourse.

2) The Gender Perspective -- Those who pushed gender into common usage do not, however, view the words as synonyms. According to theories promoted by Marxist-influenced radical feminists, gender is different than sex. Sex refers only to the biological reality of male or female, gender refers to socially constructed roles which can change. While in principle there is nothing wrong with distinguishing between the biological reality and the cultural or personal expression of masculinity and femininity, those who promote mainstreaming this gender perspective hold that all social difference between men and women are the result of oppressive stereotypes and should be eliminated so that men and women participate in every activity of society in statistically equal numbers.

While it is true that stereotypes have in the past prevented some from achieving their full potential, it is also true that there are real differences between men and women. For example, motherhood and fatherhood are not oppressive stereotypes, but natural realities with deep social and spiritual significance. Eliminate social recognition of the difference and you undermine the family and endanger children.

3) Gender Identity and Gender Expression -- Under the guise of promoting equality and non-discrimination, there is a major initiative to protect people from discrimination based on 'gender identity and gender expression.' Those promoting this argue that while sex is 'assigned' to a baby on the basis of observation of its genitals, some people do not accept the sex they were assigned. For example, a biological male may argue that, while he has a man's body, he believes he has a woman's brain. He may want his body surgically altered to resemble that of a woman or simply to dress as a woman. He may demand that his birth certificate and other documents be changed and that he be allowed to marry a man.

In the past, persons who wanted to be or thought they actually were the other sex or who rejected clothing and interests of their own sex and adopted that of the other sex were considered to be suffering from Gender Identity Disorder. Recently, this designation has been dropped in favor of Gender Dysphoria, reflecting the idea that there is nothing wrong with wanting to be the other sex so long as it doesn't make you unhappy and that if society's refusal to pretend you are the other sex makes you unhappy then society has to change. To reject the reality of one's sexual identity is to reject God's plan. Changing one's clothing and hair style, undergoing surgery cannot change a person's sex, which is indelibly written on every cell's DNA.

It is interesting to note that the transgendered frequently adopt clothing and behavior which reflects narrow stereotypical concepts of womanhood and manhood. Rejection of the reality of one's sexual identity and the pursuit of mutilating surgery suggests a severe psychological disorder. It is neither charitable nor required for others to go along with the pretence of sex change.

4) Genderqueer -- Genderqueer is a rebellion against 'compulsory heterosexuality,' -- the idea that heterosexuality is the norm. The genderqueer reject all restrictions on identity, behavior, and sexual activity and claim a right to present themselves as male, female, or neither and to change their identity at any time and to have sex with persons of either sex. According to Riki Wilchins, writing in "GenderQueer: Voices from beyond the sexual binary," "Gender is the new frontier: the place to rebel, to create new individuality and uniqueness, to defy old, tired, outdated social norms, and, yes, to occasionally drive their parents and sundry other authority figures crazy."

Those in rebellion against reality undoubtedly feel discriminated against, but society is under no obligation to honor their demands.

In his remarks Pope Benedict drew attention to a paper by Gilles Bernheim, the Chief Rabbi of France, entitled "Homosexual Marriage, Homosexual Parenting and Adoption: What we have forgotten to say," which brilliantly explains the errors of gender theory. Unfortunately, in reporting on the Holy Father's recent comments, the press has focused on his opposition to the redefinition of marriage and adoption of children by same-sex couples, ignoring the deeper philosophical issues.

One way to fight the various manifestations of gender theory is by simply not using 'gender' when we mean 'sex.'

Dale O'Leary is a freelance writer and author of "The Gender Agenda: Redefining Equality" and "One Man, One Woman."